Deputy Public Defender Mignon Hilts said the defendant had a psychotic breakdown and was using drugs just before the murders, but his parents thought they could deal with him at home rather than have him hospitalized.

"No one ever saw this coming," the defense attorney said.

The defendant shot his mother in the early morning of Nov. 28, 2014, then ambushed his father when the emergency room physician came downstairs to check on his wife.

Courtney Gant, who lives next door, testified last year that she heard screaming, yelling and what sounded like gunshots about 3 a.m. The witness said she looked down into the victims' kitchen and saw someone walking, then heard a male voice say, "He shot her in the chest. I think she's dead."

Gant said she saw the silhouette of a man consistent with Peter Haynes standing outside a sliding glass door holding a gun. She said she was on the phone with a 911 operator when she heard a man scream, then three to four more shots.

San Diego police Officer Bradford Green testified that he found Lissa Haynes' lifeless body and her wounded husband -- who had been shot nine times -- after another officer kicked in the front door. Both victims were pronounced dead at a hospital.

"He (David Haynes) said, `My son shot me,' " the officer testified.

When he asked the physician why his son shot him, the father responded, "He's schizophrenic," according to Green.